Thermostat.



G. P. lWILD.

THERMOSTAT. V APPLIUATION FILED DBIG. 7, 1910.

WITNESSES om av M1.. //m um UNITED A' STATES rA'rEN'r onirica.

GNTHER PHILIP WILD, 0F PHILADELPHIA, PENNSYLVANIA, AS'SIG-NOB. TO

FREDERICK W. SCHMIDT, 0F PHILADELPHIA,l PENNSYLVANgA. 4

THERMOSTAT.

ing in the city and county of Philadelphia,

State of Pennsylvania, have invented a new and useful Thermostat, of which the following is a specification.

My invention consists of certain improvements in a thermostat particularly adapted for use in a controlling apparatus for charging storage batteries, such as disclosed 1n Patents Nos. 976,748 and 976,750, granted to Frederick W. Schmidt, on the 22nd day of November, 1910.

It further consists of a thermostat capable of functions and possessed of properties similar to those performed and possessed by the thermostats for which Letters Patent, Nos. 976,747 and 976,749, were granted to Frederick W. Schmidt, on the 22nd day of November, 1910.

It further consists of a thermostat embodying the feature of an acid-resisting casing havingl a part of its outer surface electrically non-conductive and a part of such surface insulated or electrically conductive and exposed to the battery solution and electrically connected to one contact of the thermostat, such as disclosed and claimed in my co-pending application, Serial No.

595,284, filed on the 2nd day of December,

1910, for a thermostat.

It further consists of other novel features of construction, all as will be hereinafter fully set forth. u

For the purpose of illustrating my invention, I have shown in the accompanying drawings one form thereof which is at present preferred by me, since the same has been found in practice to give satisfactoryv and reliable results, although it will be understood that the various instrumentalities of which my invention consists can be variously arranged' and organized and that my invention is not iimited to the precise arrangement and organization of Vthese in-v strumentalities as herein shown and described.

Figure l represents a longitudinal secspeemedtin of :Meer: raten. Application led December 7, 1910. Serislllo. 596,056.

tion of a thermostat, illustrating one embodlment of my invention. Fig. 2 represents, a longitudinal section of a'thermostat, lllustratmg another embodiment of my in-v vention. Fig. 3 represents a longitudinal section of a thermostat, illustratmg still' another embodiment `of my invention.

The thermostat has a metallic base-plate, 1, usually of brass, having a short post, 2, at one end, into which one end of a composite metal thermostat-bar, 3, is secured. The freeend of said bar has a contact-point, 4, preferably of a metal fusible at a high temperature, only, which registers and may have contact, when the bar-'is flexed owingY to the difference in the co-eiicients of eX- pansi'on of the two metals from which the bar is formed, with/a contact point, 5, of the 'same metal and secured to the end of ai contact-screw, 6, threaded, to be adjusted with itsv point nearer to or. farther from the contact-point of the thermostat-bar in a yoke or bracket, 7, secured upon but insulated from the base-plate. Thebase-plate and thermostat are inclosed in the body, 8, of a casing, preferably of rectangular form, andhaving a cover, 9, secured liquid-tight to the upper edges of the side-walls.

In the forms illustrated in Figs. 1 and 2, the casing is formed from an electrically conductive but non-acid-resisting material, and the entire casing of the form illustrated in Fig. 1 is covered by a coat-ing or envelop, 10, of porcelain, enamel, lacquer, or any suitable insulating or non-conductive material. Plugs or inserts, 11,- of conductive and acid-resisting material, are inserted through the bottom of ,the casing and in electrical contact with the same and with he base-plate, and the outer surfaces of such inserts are not covered by' the insulating coating but are exposed to the battery solution to form electrodes. and plugs or inserts form a part of the casing, being intimately united with the casing, proper, whereby the exposed surface Patented Jan. 2,1912.

The envelop' of the non-acid-reslsting casing is covered..

by a coating,I 12, of porcelain, enamel, lacquer, or any suitable insulatm or nonconductive material, and thebo y of the l -casing is intimately covered by plating or other process by a deposit, 13, of electrically conductive and acid-resistingmaterial forming an electrode. A plate, 14, of acld- -resisting and electrically non-conductive material, is secured to the `outer surface of the casing to cover the bottom thereof. As the non-conductive coating for the top, the

lated deposit and the bottom plate are all lntimately united with the casing, proper, all become portions of the inclosing casing-structure which will vthus have an exosed surface which is wholly acid-resisting, m part electrically conductive, at the uncoated sides, and electrically. connected to one contact of the thermostat.v

In the form illustrated` in Fig. 3, the walls of the casin-g, or as much of' them as is eX- posed to the battery solution, are formed from acid-resisting and electrically conducvcasing for the same formed from electrically tive material, and the entire casing is covered by a coating or envelop, 15, of insulating or non-conductive and acid-resisting material, such as porcelain, enamel, lacquer or c suitable insulating material, which envelop is formed with a number of openings, 16, providing for contact by the conductive and acid-resisting exposed parts or electrodes of the casing with the battery solution.

' Like in the two above referred-to forms, the envelop is-intimately 'united with the casing, proper, the whole thus forming aV casing, the exposed surface -of which.` is wholly acid-resisting and in part electrically conductive, at the points not covered by the intimate envelop, and electrically connected to one contact of the electrode.

. In alll forms, the uncoated parts admit of the casing forming an electrode connected to one contact of the thermostat.

The cover of the casing in all of the forms has a neck, 17, the upper face of `which has annular ribs, 18.\ A binding-screw, 19, extends through the neck and has a\lange, 20,

upon it and having annular ribs, 21, upon its under side. A nut, 22, fits upon the screw and serves as a binding-nut in conjunction with theV flange. A tube, 23, of mica, insulates the screw from the opening in the neck, and a domed shield or washer, 24,'. lits upon this insulating tube and has annular corruations, 25, surrounding its central opening. askets, 26, of rubber or similar yielding material, andl having a washer, 27, of mica,

are ,interposed between the ribbed `underside of the flange upon the screw and the upper corrugated face of the shield, and similar gaskets, 28, and interposed washer, 29,

are held bet-Ween the corrugated under-side of the shield and the annularly ribbed seat l uid, such as oil or similar liquid hydro-car?,

bon, by means of which the elements within the casing are properly insulated, arcs formed between the contact-points will be extinguished, and heat will be conveyed from the exterior of the casing to the there..

mostat bar.

Having thus described my. invention, what I claim as new and desire to secure by Letters Patent, is

1. A thermostat, a concrete and unitary terial being acid-resisting. 1

2. A thermostat, a concrete and unitary casing for the same formed from electrically conductive material and having the greater part of its outer surface rendered non-conductive by an electrically non-conducting and acid-resisting coating, and an acid-re.

sisting electrode electrically' connected to one l element of the thermostat and uncovered by;

thereof electrically non-conductive and a part of the same electrically conductive to lform an electrode connected to one of the elements of the'thermostat. l

5. A-thermostat, a concrete and unitary casing for the same forming an electrode electrically connected to one element 'of the thermostat and having its outer surface wholly acid-resisting and the greater part thereof electrically non-conductive and having a portion exposed through the non-conductive surface.

6. A thermostat, a concrete and unitary casing for the same having its outer exposed surface acid-resisting and electrically nonconductve and formed with vacid-resisting and electrically;conductive inserts forming parts of the walls of the casing and e1ectri' 10 cally "connected to one element of the thermostat and extending to be exposed through the non-cond1rctiie surface of the casing.

GNTHER PHILIP WILD. z

Witnesses:

C. D. MOVY, F. A. NEWTON. 

